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51.
几种饲料作物在内蒙古呼和浩特地区的生产性能评价   总被引:4,自引:2,他引:2  
李青丰  徐军  李治国 《草业科学》2003,20(12):22-25
在内蒙古呼和浩特地区,种植并评价了6种(品种)饲用高粱和高丹草类植物的生产性能及作为饲用植物的价值。结果表明,此类植物具有高产、饲用价值高、利用方便等特点,应用前景广阔,可以考虑作为饲用玉米和苏丹草类植物的换代产品。从植物产量、叶量和分蘖特性等方面综合考虑,饲用高粱大力士和高丹草健宝明显优于其他品种,可以作为该地区的首选推广品种。  相似文献   
52.
A primary lung tumor in a dog treated with intensity-modulated radiation therapy was imaged approximately 6 weeks and 1-year posttreatment with combined positron emission tomography (PET) and computed tomography, utilizing the radiotracers 18F-fluorodeoxyglucose and 18F-fluorothymidine. These two tracers allowed discrimination of tumor from inflammation, and demonstrated spread of tumor along airways over time after treatment. Fusion of functional imaging with anatomic imaging is a useful tool, particularly in the field of oncology, with the potential for PET markers that delineate tumor from normal or reactive tissue, and potential or actual response to therapy.  相似文献   
53.
54.
Inhibition of tumour growth and angiogenesis by targeting key growth factor receptors is a promising therapeutic strategy for central nervous system tumours. Characterization of these growth factor receptors in canine primary brain tumours has not been done. Using quantitative real‐time TaqMan polymerase chain reaction (PCR), we evaluated the expression of messenger RNA (mRNA) for five tyrosine kinase growth factor receptors (vascular endothelial growth factor receptor [VEGFR]‐1, VEGFR‐2, endothelial growth factor receptor [EGFR]‐1, platelet‐derived growth factor receptor a [PDGFRa], and c‐Met) relative to normal cerebral cortex in 66 spontaneous canine primary brain tumours. Increased expression of VEGFR‐1 and VEGFR‐2 mRNA was greatest in grade IV astrocytomas (glioblastoma multiforme) and grade III (anaplastic) oligodendrogliomas. EGFR‐1 mRNA expression was more consistently increased than the other receptors in all tumour types, while increased PDGFRa mRNA expression was mostly restricted to oligodendrogliomas. The similarities in increased expression of these tyrosine kinase growth factor receptors in these canine tumours, as compared to data from their human counterparts, suggest that common molecular mechanisms may be present.  相似文献   
55.
四子王旗草场生产潜力与载畜量调控研究   总被引:5,自引:1,他引:4  
文章对四子王旗草场牧草生产量与载畜量现状相关性和草场牧草生产潜力与载畜量相关性进行分析、计算的基础上,提出了全旗草场载畜量调控建议。  相似文献   
56.
全球气候变化对松嫩草原土壤水分和生产力影响的研究   总被引:6,自引:1,他引:5  
邓慧平  祝廷成 《草地学报》1998,6(2):147-152
本文首先模拟计算松嫩草原土壤水量平衡,并结合未来气候情景估算松嫩草原土壤水分的变化。最后,在土壤水分研究的基础上,初步评估全球气候变化对松嫩草原生产力的影响。  相似文献   
57.
A pedigree analysis of a family of 15 related Chinese Shar Peis was conducted. This pedigree analysis, including affected and nonaffected dams, sires and offspring, was compiled to document and characterize the occurrence, common clinical signs, and age of onset of primary lens luxation while suggesting a possible mode of inheritance in this breed. Of the five offspring from the mating of an affected dam to two unrelated affected males, 100% of offspring were affected with bilateral primary lens luxations. Of the four viable offspring from the mating of the same affected dam to an unrelated, unaffected male, two dogs (50%) were affected. The average age of onset of affected animals (seven) in this first generation was 4.9 years (range 3–6 years). The six dogs in the second generation of the same pedigree line were 2-years-old at examination with none of these animals affected at the time of this study. The most common presenting complaints were a unilateral change in ocular appearance (5 of 7 dogs) and subjective vision impairment (4 of 7 dogs). The most common clinical sign upon ophthalmic examination was iridodonesis (unilateral 4 of 7 dogs; bilateral 3 of 7 dogs) and the presence of an aphakic crescent (3 of 7 dogs). Gonioscopy and tonometry of severely affected eyes revealed a narrow or closed iridocorneal angle and ocular hypertension. This study suggests that primary lens luxation does occur in the Chinese Shar Pei, resembling the clinical condition (age of onset, clinical signs) previously described in the terrier breeds, the Border Collie, and the Tibetan Terrier. Application of the phenotypic findings in this study to a Mendelian genetic model of inheritance suggests that primary lens luxation in the Chinese Shar Pei is inherited as a simple autosomal recessive trait.  相似文献   
58.
藏鸡的现状及利用   总被引:4,自引:0,他引:4  
许锋 《四川畜牧兽医》2000,27(Z1):111-112
藏鸡是一种体型较小、胸腿发达、快羽 ,适宜于高寒、低压、缺氧高海拔地区的地方优良品种 ,素以觅食能力强 ,极耐粗放 ,体小肉多、肉质细嫩鲜美而著称 ,是高海拔地区养禽业中的当家品种。针对藏鸡生产、繁育的现状和不足 ,分析其制约因素 ,研究搞好藏鸡繁育与饲养的综合配套技术以及藏鸡可持续开发利用的战略对策 ,无疑具有现实的指导意义和长远的理论意义  相似文献   
59.
Rangelands are vital for wildlife conservation and socio‐economic well‐being, but many face widespread degradation because in part of poor grazing management practices. Planned grazing management, typically involving time‐controlled rotational livestock grazing, is widely touted as a tool for promoting sustainable rangelands. However, real‐world assessments of its efficacy have been lacking in communal pastoral landscapes globally, and especially in Africa. We performed landscape‐scale assessment of the effects of planned grazing on selected vegetation, wildlife, and cattle attributes across wide‐ranging communally managed pastoral rangelands in northern Kenya. We found that planned grazing enhanced vegetation condition through a 17% increase in normalized difference vegetation index, 45–234% increases in herbaceous vegetation foliar cover, species richness and diversity, and a 70% reduction in plant basal gap. In addition, planned grazing increased the presence (44%) and species richness (53%) of wild ungulates and improved cattle weight gain (>71%) during dry periods when cattle were in relatively poor condition. These changes occurred relatively rapidly (within 5 years) and despite grazing incursion incidents and higher livestock stocking rates in planned grazing areas. These results demonstrate, for the first time in Africa, the positive effects of planned grazing implementation in communal pastoral rangelands. These improvements can have broad implications for biodiversity conservation and pastoral livelihoods. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
60.
王建斌 《北京农业》2012,(6):240-241
笔者从石灰土在道路施工中的重要性出发,分析市政道路石灰土基层施工的前期准备工作,并介绍了市政道路石灰土基层施工工艺流程,最后分析了特殊季节道路石灰土基层施工的注意事项。  相似文献   
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